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[Display omitted] • Micelles were in situ incorporated into the thin film nanocomposite (TFN) membrane. • The stable and monodispersed micelles can essentially regulate the interfacial polymerization (IP) process. • The structure of polyamide layer was optimized by further refinement of the IP process. • The resultant TFN membrane exhibited high water permeance (20.7 L m-2h−1 bar−1) and superior Na 2 SO 4 rejection (99.3 %). The desalination performance of thin film nanocomposite (TFN) membranes is significantly influenced by the nature of nanofillers and the structure of the polyamide (PA) layer. Herein, a micelles regulated interfacial polymerization (MRIP) strategy is reported for the preparation of TFN membranes with enhanced nanofiltration (NF) performance. Specially, stable and ultrafine micelles, synthesized from the poly(ethylene oxide)- b -poly(4-vinyl pyridine)- b -polystyrene (PEO-PVP-PS) triblock copolymers, were utilized as regulators in the aqueous phase during the interfacial polymerization (IP) process. TFN membranes were fabricated with varying concentrations of micelles to improve their properties and performances. The structure of the PA layer was further regulated by modulating the content of trimesoyl chloride (TMC), which significantly enhances the performance of the TFN membrane with micelles. Attributable to the homogeneously dispersed micelles and the modified PA layer, the optimized membrane denoted as TFN-2–0.3 exhibits an improved separation performance of 20.7 L m-2h−1 bar−1 and 99.3 % Na 2 SO 4 rejection, demonstrating nearly twice the permeance and 2.7 % higher rejection than that of the original control membrane, respectively. The mechanism of this MRIP strategy was investigated through the diffusion experiments of piperazine (PIP) and interfacial tension tests. The incorporated micelles effectively lower the interfacial tension, promote the diffusion of PIP and accelerate the IP reaction, resulting in a denser and thinner PA layer. Collectively, these findings demonstrate that TFN membranes with micelles exhibit increased roughness, enhanced hydrophilicity, superior rejection to divalent salts, and better acid-base resistance, highlighting their potential applications in the design of TFN membranes. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori (H. pylori) causes chronic gastric disease. An efficient oral vaccine would be mucosa-targeted and offer defense against colonization of invasive infection in the digestive system. Proteolytic enzymes and acidic environment in the gastrointestinal tract (GT) can, however, reduce the effectiveness of oral vaccinations. For the creation of an edible vaccine, L. lactis has been proposed as a means of delivering vaccine antigens. Results: We developed a plSAM (pNZ8148-SAM) that expresses a multiepitope vaccine antigen SAM-WAE containing Urease, HpaA, HSP60, and NAP extracellularly (named LL-plSAM-WAE) to increase the efficacy of oral vaccinations. We then investigated the immunogenicity of LL-plSAM-WAE in Balb/c mice. Mice that received LL-plSAM-WAE or SAM-WAE with adjuvant showed increased levels of antibodies against H. pylori, including IgG and sIgA, and resulted in significant reductions in H. pylori colonization. Furthermore, we show that SAM-WAE and LL-plSAM-WAE improved the capacity to target the vaccine to M cells. Conclusions: These findings suggest that recombinant L. lactis could be a promising oral mucosa vaccination for preventing H. pylori infection. [ABSTRACT FROM AUTHOR]

Incorporation of nanosized metal organic frameworks (MOFs) fillers into polyamide layer can essentially enhance the performance of thin film nanocomposite (TFN). However, in situ growth of MOFs during interfacial polymerization (IP) is impeded by the insolubility of metal precursors in alkaline aqueous solutions. Herein, 1,4,7,10-tetraazacyclododecane (Cyclen), a macrocyclic polyamine capable of complexing metal ions, was integrated into the IP process to fabricate TFN membranes with in situ synthesized zeolitic imidazolate framework-8 (ZIF-8). Compared to the conventional piperazine-trimesoyl chloride (PIP-TMC) membrane, the modified PIP + Cyclen-TMC membrane features a thinner and denser polyamide layer. After the incorporation of ZIF-8, the polyamide layer becomes looser, more hydrophilic and electronegative. The resultant TFN membranes demonstrated exceptional water permeance (31.4 L m−2 h−1 bar−1) and improved selectivity (96.3 %), signifying a permeance enhancement of 182.6 % compared with that of the pristine PIP-TMC membrane. Additionally, the optimized membrane manifested enhanced fouling resistance and long-term stability. This macrocyclic polyamines mediated in situ growth technique can be extended to other combinations of macrocyclic polyamines and metal precursors, offering a novel paradigm for the fabrication of TFN-MOFs membranes for desalination. [Display omitted] • Macrocyclic polyamines were used to mediate the growth of MOFs during interfacial polymerization. • The introduction of macrocyclic polyamines (Cyclen) can effectively regulate the formation of polyamide layer. • In situ formed nanosized ZIF-8 were well dispersed into polyamide layer through the complexation between zinc and Cyclen. • The optimized membrane exhibited superior water permeance (31.4 L m−2 h−1 bar−1) and improved Na 2 SO 4 rejection (96.3 %). [ABSTRACT FROM AUTHOR]

Defect-engineered UiO-66-NH2 was introduced into a polyamide layer to form a thin film nanocomposite (TFN) membrane. Simultaneous enhancements in permeance and selectivity to Na2SO4 solution were achieved. [ABSTRACT FROM AUTHOR]

The performance of mixed matrix membranes (MMMs) substantively depends on the intrinsic structure and composition of the introduced nanofillers. In this work, pyrazole-based metal-organic frameworks (termed as MOF-303) were introduced into polymer of intrinsic microporosity (PIM-1) through a physical blending approach. Thanks to the well CO 2 -philic capability, high porosity, and appropriate pore structure of the incorporated MOF-303, the obtained MMMs exhibited remarkable separation performance. The improved CO 2 permeability and well-maintained CO 2 /CH 4 selectivity were achieved. Specifically, MMMs introducing 30 wt% MOF-303 loading exhibited a CO 2 /CH 4 selectivity of 27.6 and a high-CO 2 permeability of 7528.2 Barrer, which were 2.2 and 1.9 times greater than those of the unfilled PIM-1 membranes, respectively. Furthermore, a 33-h continuous separation test verified the excellent stability of the manufactured MMMs. More importantly, the MMMs showed significant resistance against physical aging, retaining up to 92.8% of their original CO 2 permeability after 150 days, compared to just 33.0% for control PIM-1 over the same period. Meanwhile, the plasticization resistance of the MMMs was reinforced compared to the unfilled PIM-1 membrane. This study potentially provides a novel approach for the rational design of MMMs in CO 2 separation applications. [Display omitted] • The CO 2 -philic MOF-303 nanofillers provided fast and selective transport channels for CO 2. • The prepared MMMs exhibit increased CO 2 permeability and CO 2 /CH 4 selectivity by 90.8% and 120.8%, respectively. • Long-term stable CO 2 /CH 4 separation and good antiaging performance were achieved. • MOF-303 improves CO 2 permeability by simultaneously enhancing solution and diffusion transport. [ABSTRACT FROM AUTHOR]

The performance of mixed matrix membranes (MMMs) is significantly determined by the inherent structure and composition of incorporated nanofillers. In this work, the core-shell ZIF-8@RF nanofillers were prepared through a kinetically-controlled growth of zeolitic imidazolate framework-8 (ZIF-8) and polymerization of resorcinol and formaldehyde (RF), followed by being incorporated into the glassy 6FDA-Durene and rubbery Pebax 1657 via a physical blending approach to form MMMs. Benefiting from the enhanced interfacial compatibility, CO 2 affinity, and the intrinsic characteristics of porous ZIF-8, the resultant MMMs demonstrated outstanding performance for CO 2 /CH 4 separation. The CO 2 permeability and CO 2 /CH 4 selectivity of the ZIF-8@RF/6FDA-Durene (ZIF-8@RF/Pebax 1657) MMMs increased up to 1332.1/363 Barrer and 28.6/29.6, corresponding to an improvement of 65.4/116.3% of the CO 2 permeability and 49.7/53.4% of the CO 2 /CH 4 selectivity compared to the pristine membrane. Meanwhile, CO 2 /CH 4 selectivity of ZIF-8@RF MMMs increases by up to 33.0% and 28.1% in comparison to the ZIF-8 without RF layer MMMs, respectively. More importantly, both MMMs can maintain their extraordinary separation performance after stabilized in the existence of moisture. These results demonstrate that the separation performance of the MMMs was remarkably improved with the addition of ZIF-8@RF. [Display omitted] • Interface regulation was achieved by formed H-bonding between two families of mixed matrix membrane. •The prepared MMMs exhibit increased CO 2 permeability and CO 2 /CH 4 selectivity by 65.4/116.3% and 49.7/53.4%, respectively. • The improved CO 2 /CH 4 selectivity origins from the remarkable increase of diffusion selectivity. •Both MMMs maintained their impressive separation performance after being stabilized in the presence of moisture. [ABSTRACT FROM AUTHOR]

Rational design of fillers and polymers is of great importance to fabricate mixed matrix membranes (MMMs) with high performance. In this work, fluorinated metal-organic frameworks (KAUST-7 (also referred as NbOFFIVE-1-Ni)) were adopted as nanofillers to prepare MMMs through physically blending into the polymer of intrinsic microporosity (PIM-1). Benefiting from the features of porous KAUST-7, including well CO 2 affinity, distinctive pore characteristics (size, shape, and functionality) and strong intermolecular interactions with PIM-1, the achieved MMMs demonstrated increased CO 2 /CH 4 separation performance and improved anti-physical aging property. Specifically, with the assistance of KAUST-7, the CO 2 permeability and CO 2 /CH 4 (30:70 vol%) selectivity of the optimized MMMs increased up to 5928 Barrer and 23.5, corresponding to improvements of 50% of and 88% of the permeability and selectivity compared with the pristine membranes, respectively. Importantly, 100-h continuous separation test results confirmed the satisfying long-term stability of the prepared MMMs. Notably, the MMMs maintained 91% of the initial CO 2 permeability after 150 days (decreased only 539 Barrer), implying that the CO 2 permeability decrement is about 5-fold lower than that of the control PIM-1 membrane. These results suggest that the fabricated MMMs are promising candidates for CO 2 separation in practical applications. [Display omitted] • The CO 2 -philic KAUST-7 fillers were incorporated to PIM-1 for fabrication of MMMs. • The resultant MMMs exhibit enhanced CO 2 permeability and selectivity. • Long-term stable CO 2 /CH 4 separation and good antiaging performance were achieved. • Good interfacial compatibility between fillers and polymers results in the enhanced performance. [ABSTRACT FROM AUTHOR]

The performance of polyamide-based thin film nanocomposite (TFN) membranes essentially hinges on nanofillers, polyamide (PA) selective layer and the interaction between them. Incorporating synthesized nanofillers into PA layer has attracted significant attention, yet this fabrication route suffers from the unsatisfactory interfacial compatibility between nanofillers and polymer matrix. As pure organic nanofillers, covalent organic frameworks (COFs), however, are constrained by their large pore size and demanding synthesis condition. Herein, COF TpHz was synchronously synthesized with the interfacial polymerization (IP) process of PA layer to fabricate COFs incorporated TFN membranes. The addition of TpHz was optimized by controlling the content of monomers and the resultant TFN membrane achieved enhanced nanofiltration performance thanks to the in-situ synthesized TpHz. At ambient temperature, the prepared membrane showed higher permeance (23.6 L m2 h−1 bar−1) and salt rejection (96.9%) than the pristine thin film composite (TFC) membrane under 4 bar toward 1 g/L Na 2 SO 4 solution, corresponding to an improvement of 44.8% and 3.2% of permeance and rejection, respectively. Meanwhile, the anti-fouling property of the prepared membrane was also improved compared with TFC membrane. This in-situ interfacial polymerization (IIP) strategy proposes a new idea for the preparation of COFs incorporated TFN membranes, revealing its promising prospect in desalination. [Display omitted] • Synchronization formation strategy on the polyamide and covalent organic frameworks (COFs) is proposed. • COFs were in-situ synthesized under a mild condition and characterized by visualized method. • The resultant novel membrane exhibited high water permeance (23.6 L m−2 h−1 bar−1) and Na 2 SO 4 rejection (96.9%). • The combined effect of polyamide and multi-layer COFs on desalination performance is discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Functional layer veiled ZIF-67(VZIF-67) nanofillers was blended with 6FDA-Durene polyimide to fabricate MMMs. • The compatibility of VZIF-67 in 6FDA-Durene membranes is significantly improved by the Functional layer assisting. • The resultant VZIF-67/6FDA-Durene MMMs exhibits improved CO 2 separation efficiency. • The CO 2 /CH 4 separation performance of membranes surpasses the Robeson's upper bound. The interfacial compatibility between fillers and polymers essentially influences the separation performance of mixed matrix membranes (MMMs). In this work, an one-pot synthesized functional layer veiled zeolite imidazolate frameworks-67 (VZIF-67) was used as an efficient nanofillers to fabricate MMMs via physical blending with 6FDA-Durene polyimide. Benefiting from the CO 2 affinity from functional layer and the intrinsic characteristics of porous nanofillers, significant enhancement on separation performance was observed on the resultant MMMs. Specifically, the optimized VZIF-67 MMMs (30 wt% loading) exhibited CO 2 /CH 4 selectivity of 32.5 with CO 2 permeability of 1210 Barrer, which is 1.7 and 1.5 times higher than those of the control membrane, respectively. More importantly, the surface organic attribute and abundant amine groups of VZIF-67 reinforced the interfacial compatibility between the nanofillers and polymer matrix, leading to a doubled CO 2 /CH 4 selectivity compared with the ZIF-67 MMMs. Overall, the performance of the VZIF-67 membrane toward CO 2 /CH 4 separation surpasses the 2008-updated Robeson upper bound. These results indicate the functionalization strategy on porous nanofillers is a promising approach to fabrication of high performance of MMMs. [ABSTRACT FROM AUTHOR]

Background: Helicobacter pylori (H. pylori), a specific bacterium capable of surviving in the acidic environment of the stomach, has been recognized as a group of causative agents of gastric cancer. Therefore, the development of mucosal vaccines against H. pylori is expected to provide an important direction for the treatment of chronic gastritis and the prevention of gastric cancer. Methods and results: In this study, we used bacteria-like particles (BLPs) obtained by treating Lactic acid bacteria (L. lactis) with hot acid, and successfully displayed the M cell-targeted H. pylori multi-epitope purified antigen SAM-FAdE, with 90% display efficiency. In addition, BLPs-SAM-FAdE can effectively target M ​​cell models and M cells of mouse Peyer's patches (PPs) through oral immunization, promote the transport of particulate vaccines to dendritic cells (BMDCs) and stimulate their maturation, significantly increased proportion of plasma cells and germinal centers B cells. This indicates that the vaccination can induce notable antigen-specific mucosal immune responses (production of sIgA), CD4+ T cell responses (Th1/Th2/Th17) and humoral immune responses (production of serum IgG). Furthermore, oral BLPs-SAM-FAdE dramatically reduced the H. pylori adhesion and specific 16S rRNA expression of H. pylori in gastric mucosal tissue, protecting gastric tissue from damage. Conclusion: BLPs-SAM-FAdE can significantly reduce the adhesion of H. pylori in gastric mucosal tissue and inhibit gastritis and gastric damage caused by H. pylori infection. [ABSTRACT FROM AUTHOR]

[Display omitted] • The intrinsic properties of photocatalysts can be tuned by NH 2 -MIL-125 derived nitrogen-doped titania/carbon (NTC) catalysts. • Visible light-driven NTC enhanced PMS utilization efficiency for SMT degradation. • The PMS activating mechanism on NTC catalysts was elucidated. • Photo-electrons excited from NTC played the dominant role for the enhancement of PMS utilization efficiency. Enhancing the utilization efficiency of oxidant is of great importance for advanced oxidation processes (AOPs). Herein, nitrogen-doped titania dioxide/carbon (NTC7) catalyst was fabricated via pyrolyzing NH 2 -MIL-125 under nitrogen atmosphere at 700 °C. Excitation of NTC7 under visible light can successfully achieve efficient activation of peroxymonosulfate (PMS) (NTC7 + PMS + Vis). Degradation performance and PMS activation mechanism were systematically investigated using sulfamethazine (SMT) as the target pollutant. It was found that the photo-generated electrons excited from NTC7 under visible light played the dominant role in enhancing the productive consumption of PMS. Its utilization increased by 66 % (Δ[PMS]/Δ[SMT] = 7.0) in NTC7 + PMS + Vis process and the degradation rate was 2.14 times higher than that of NTC7 + PMS process. The ketonic C O groups and structural defects were responsible for the generation of 1O 2 in dark activation while radicals (•OH, O 2 •–) were more inclined to be continuously produced in NTC7 + PMS + Vis process. The involved degradation pathways, intermediates, and toxicity assessment have been studied in detail. This work provides an effective approach to enhance the utilization efficiency of oxidant for pollutant degradation by AOPs. [ABSTRACT FROM AUTHOR]

Zirconium-based metal–organic framework nanosheet assembled hydrangea-like architectures were reported and an enhanced iodine capture capacity was achieved. [ABSTRACT FROM AUTHOR]

Nanofiltration (NF) is an advanced environmental technology in water treatment. To thin film nanocomposite (TFN) membrane, good compatibility between nanofillers and polyamide (PA) layer is the guarantee of remarkable performance. Herein, tannic acid (TA) was employed as modifier of UIO-66-NH 2 prior to the interfacial polymerization (IP). With TA modification, more interaction can be formed so that the compatibility between nanofillers and PA layer can be promoted at the molecular level. Characterizations demonstrated the coating of TA on UIO-66-NH 2 , together with successful introducing of nanofillers in TFN membranes. Compared to pristine thin film composite (TFC) membrane, both UIO-incorporated TFN (TFN-U) and TA modified UIO-incorporated TFN (TFN-TU) membranes showed higher permeance (111.2% and 93% enhancement, respectively). However, under the same nanofillers dose, TFN-TU exhibited slightly lower permeance and higher rejection than TFN-U since the bridging effect of TA healed non-selective voids in skin layer. With the increasing of nanofiller dose in IP, TFN-TU remained reasonable selectivity while TFN-U failed to. Moreover, TFN-TU showed better anti-fouling property due to TA modification. Introducing TA modified MOFs into IP can serve as an ingenious strategy for TFN membrane to achieve high-quality environmental applications. • Tannic acid modified UIO-66-NH 2 was incorporated in TFN membrane (named as TFN-TU). • Interactions between membrane and fillers were improved via reactions of tannic acid. • TFN-TU membrane exhibited enhanced NF performance and anti-fouling property. • The superior performance is due to the bridging effect of tannic acid. [ABSTRACT FROM AUTHOR]

• Dual-functional ultrafiltration (DFUF) membrane is fabricated by nanoadsorbents loading. • Hollow mesoporous carbon nanospheres were loaded into the finger like pores of polymeric UF membrane. • Multi-pollutants can be synchronously removed under low pressure and high flux by DFUF membranes. • The DFUF membrane possesses excellent reusability. An effective way to remove micropollutants is desirable for water purification. In this work, a dual-functional ultrafiltration (DFUF) membrane was fabricated by loading hollow mesoporous carbon nanospheres (HMCNs) into the finger-like support layer pores of the polymeric ultrafiltration (UF) membrane. The designed DFUF membrane combines the high selectivity of ultrafiltration that removes macromolecules based on size exclusion mechanism, and excellent adsorption capacity of HMCNs towards micropollutants in water. When tetracycline (TCN) and 17β-Estradiol (E2) were selected as model micropollutants, corresponding 97 % and 94 % removal were achieved at a low pressure less than 0.15 bar and a flux of 50 and 64 L h−1 m-2 (estimated residence time less than 6 s), respectively. Moreover, simultaneous removal of multiple pollutants was demonstrated by filtering a mixture containing TCN and polyethylene glycols (PEG) 600 kDa macromolecules. Over a long filtration period (more than 60 h) that produced 3180 L/m2 of permeate, the TCN concentration reduced from 100 μg/L in the feed to less than 10 μg/L in the permeate. The above results indicate that the DFUF membrane is capable of removing the small molecular and macromolecular pollutants simultaneously at low pressure, and hence offers remarkable potential in water treatment applications. [ABSTRACT FROM AUTHOR]

In this work, a novel tannic acid assisted interfacial polymerization (TAIP) method was developed for preparing loose nanofiltration membranes (LNMs). Piperazine (PIP) and tannic acid (TA), two kinds of common monomer for interfacial polymerization (IP), were employed to deposit on substrate for the TAIP process. The TAIP process resulted in enlarged pores in the skin layer due to the longer monomers, thus achieved considerable permselectivity in separating salts from dye/salt mixture solution. The optimal TAIP membrane (M4) exhibited high permeability (32.57 LMH·bar−1 to Congo Red solution), reasonable rejection to dyes (99.40% and 99.19% for Congo Red and Rose Bengal, respectively) and satisfactory transport to salts (90.59% to Na 2 SO 4 and 97.75% to NaCl). Meanwhile, this membrane retained high performance in dye/salt separation (7.16 LMH·bar−1 of permeability, 97.47% of CR rejection and 2.55% of NaCl retention) under even as high as 6 wt% of salt concentration. Moreover, TAIP LNM showed high stability throughout a 30-hour-long running test to separate salts from dye/salt mixture solution. We anticipated the TAIP methodology, together with the consequential LNM, to provide a potential candidate for dye/salt separation application. Unlabelled Image • A tannic assisted IP method for preparing loose NF membrane is reported. • Piperazine and tannic acid were mixed to enlarge the membrane surface pores. • The obtained membrane exhibited high flux without obvious loss of dye rejection. • Over 90.0% salt was permeated while 99.40% dye was rejected in dye/salt mixture. [ABSTRACT FROM AUTHOR]

The performance of thin film nanocomposite (TFN) membranes is substantively determined by the structure, composition and size of the incorporated nanofillers. In this work, an asymmetric organic nanofiller, resorcinol-formaldehyde nanobowls (RFB), was firstly designed via a modified Stöber approach and introduced into the polyamide selective layer of the TFN membrane via an interfacial polymerization process. Thanks to the asymmetric structure, concave cavity and chemical groups of the incorporated RFB, enhanced nanofiltration performance of the prepared TFN membrane was achieved. The optimized TFN membranes exhibited higher water fluxes and well maintained salt rejections. The water fluxes of the TFN-B0.12 membrane were 119.74 ± 4.28 for the Na 2 SO 4 solution and 141.46 ± 5.92 L/(m2·h) for the MgCl 2 solution, which are 1.5 times higher than that of the control thin film composite (TFC) membrane, with comparable rejection (95.76 ± 0.29%) for Na 2 SO 4 and 4.63% higher (25.98 ± 0.45%) rejection for MgCl 2 , respectively. Meanwhile, the basic resistance of the RFB modified TFN membrane was reinforced simultaneously as compared with that of the control TFC membrane. The results demonstrate the incorporation of the RFB significantly strengthened the nanofiltration performance of the TFN membrane. Image 1 • Resorcinol-formaldehyde nanobowls (RFB) were synthesized via a modified Stöber approach. • RFB nanofillers were embedded into the polyamide layer to fabricate thin film nanocomposite (TFN) membranes. • The prepared TFN membranes exhibit enhanced permeability and basic resistance. • The enhanced performance stems from the structural and compositional characteristics of the incorporated RFB nanofillers. [ABSTRACT FROM AUTHOR]